Flame arrester

Abstract

A highly efficient flame arrester adapted for use in preventing an external flame from backflashing upstream in a pipe, or a conduit, or a stream carrying a flammable substance. The flame arrester comprises a contained layer of nested ellipsoids formed from expanded metal sheets made from magnesium alloy foil. The arrester is useful in fuel tanks, combustion systems, sea-going tankers, hot water, or space heaters, and the like.

Description

BACKGROUND AND PRIOR ARTThe present invention relates to a flame arrester or firecheck device that is adapted to prevent a backfire from traveling upstream through a stream of flammable gas, and thus prevent unwanted fire or explosion that might otherwise be caused by the backfire.A flame arrester is a passive device that permits the flow of gas, but prevents any external flame or backfire from "flashing back" through the flow of gas to the source of flammable material. If such a flashback is not prevented, the reservoir of flammable material would ignite, resulting in a destructive fire or explosion. Devices to prevent the passage of flame are critical to processes where flammable chemicals or vapors or handled, such as in petrochemical refineries, pipelines, sea-going tankers, combustion systems, hot water heaters, space heaters, and the like.An example of an application requiring the use of a flame arrester is the vent opening normally provided on storage tanks containing oil, ga...

AI Technical Summary

Benefits of technology

The magnesium alloy flame arrester demonstrates superior flame arresting capabilities, resisting temperatures up to 1200°C and surviving shock waves, eliminating the need for costly valve mechanisms and reducing maintenance, while maintaining efficient gas flow without adjustment.

Problems solved by technology

If such a flashback is not prevented, the reservoir of flammable material would ignite, resulting in a destructive fire or explosion.

A difficulty which is commonly encountered is that most open-structured configurations which possess the required internal passage dimensions for successfully arresting a flame are able to survive the heat of the flame for only a limited time.

When unwanted ignition takes place, there is normally a continued burning on the emergent face of the arrester over a relatively long period of time while the source of burning vapors is still present.

Such extended exposure to the high temperature of the flame is normally destructive of the arrester, and therefore it is common practice to provide mechanical or other means responsive to the temperature of the arrester for closing a valve or otherwise shutting off the source of burning vapors.

However, the need for the mechanical or other means introduces additional expense, constant service and maintenance, and an additional array of moving parts which can malfunction,

A further difficulty is that, under certain ignition or detonation conditions, a rapidly developing shock wave will precede the flame front and can damage or completely destroy the open-structured configurations of the flame arrester elements before they have an opportunity to perform their flame arresting function.

According to data gathered by the U.S. Consumer Product Safety Commission (CPSC), between 1984 and 1988, there were an estimated 40,000 fires involving residential gas-fired water heaters, resulting in 200 deaths, 3,000 injuries, and $500 million in property loss, statistics which make this appliance eminent as a fire hazard.

The most probable cause for many of the fires was the ignition of "fugitive" flammable atmospheres surrounding properly operating water heaters.

The fugitive flammable substance most often accidentally ignited by water heaters was gasoline, stored / spilled and handled / mishandled in garages, where water heaters are typically installed when a house has no basement.

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